This invention relates to hand tools and more particularly to a sanding block for hand sanding operations normally used with power belt sanders.
Sanding operations, particularly manual sanding operations for smoothing and abrading metal and wood surfaces, are commonly accomplished by use of cloth or paperbacked abrasive materials. These materials, commonly termed sandpaper, can be used without a sanding block but are generally more efficient and require less effort when used in conjunction with a sanding block. Sanding blocks may simply be a rectangular section of wood, such as a section of a 2.times.4, to which the sandpaper is applied. Sanding blocks may also be specially configured blocks having a curved resilient surface which receives the paper and has fastening means at opposite ends of the block. The fastening means are generally in the form of a spring or sharp projections, which pierce the sandpaper to secure it in place.
While sanding blocks such as the type described above are convenient to use with sheets or strips of sandpaper. It is also desirable to use abrasive material of the endless belt-type for hand sanding. The endless belt-type sanding material is generally intended for use with power sanders and therefore, is generally more durable having a longer usable life. Also, the endless belt-type of abrasive material has the advantage in that it may be advanced to replace a worn section of the sanding material with an unused section. There are a number of patents in the prior art which relate to appliances or devices for sanding work surfaces that are blocks having several sections or components to accommodate an endless sanding belt. Typical prior art patents representative of devices of this type are the following:
U.S. Pat. No. 3,510,991 shows a sanding block for a continuous loop sanding belt. The block has first and second ends positioned within the belt with cam members positioned between the blocks. The cam members may be adjusted to force the blocks away from one another to secure the sanding belt in place.
U.S. Pat. No. 3, 601,933 shows a sanding block for a continuous loop sanding belt. The block has screw jack elements to loosen and tighten the belt in place.
U.S. Pat. No. 4,242,843 shows a sanding block of the general type shaped to provide a wedging action to tension the belt.
U.S. Pat. No. 4,525,959 disdoses a hand held sanding tool for use with a continuous sanding belt. The tool has a unitary fork member with a removable edge that combine to retain the belt in place. The adjoining planar surfaces are angularly related to facilitate finishing operations.
U.S. Pat. No. 5,383,308 shows a hand held sanding block formed by two blocks of like sections disposed in co-planar relationship. The blocks are freely movable towards and away from each other by means of a pair of spaced dowel pins projecting from one block in telescoping engagement in spring loaded sockets in the other block.
U.S. Pat. No 5,387,251 shows an endless belt sanding block which has a hinge construction.
Known prior art, as exemplified by the above referenced patents, do not provide a simple, inexpensive sanding block. For example, the sanding blocks described in '991,'933,'959,'251, and '308 patents have many parts making them more costly and complicated to manufacture. The '843 patent, although very simple in construction, still requires more than two parts and does not allow for just two identical parts to create an efficient sanding block like the present invention. Furthermore, the '843 patent does not provide a solid backed sanding surface on both the top and bottom surfaces of the sanding block.